Typewriting machine



May 14,1929. NEPPER 1,712,514

TYPEWRITING MACHINE Filed Jan. 14, 1927 4 Sheets-Sheet 1 fl vekf Erwin/jf er May 14, 1929. F. NEPPER TYPEWRITING MACHINE Filed Jan. 14, 1927 4SheetsSheet 2 Li/eM Z OK I May 14, 1929.

F. N EPPER TYPEWRITING MACHINE Filed Jan; 14, 1927 4 Sheets-Sheet 3 y1929- F. NEPPER TYPEWRITING MACHINE filed Jan. 14, 1927 4 Sheets-Sheet 4Inve'nfok:

.Fr-navzaz N w Patented May '14,. 1929.

UNITEDgSTATES PATENT OFFICE.

FEBNAND NEI'IPEB, 0F BRUSSELS, BELGIUM.

zrvrnwnrrme mourns.

Application filed January 14, 1927, Serial No. 161,164, and in FranceJanuary 20, 1926.

The present invention relates to the escapement action of typewritingmachines, and it consists more particularly in the provision of animproved difl'erential device which permits the escapement to beactuated a little.

struck has completed its movethe typewriting machine as regards thespeed and accuracy of the writing. Not only are the type bars made totravel at a higher speed, and the escapement actuated at a morefavorable moment, but the touch remains light and pleasant.

' The following description, with reference to the accompanyingdrawings, given by way of example, will enable the manner in which theinvention is carried into eifect to be clearly understood.

Figure 1 is a diagrammatic side view showing the invention 7 applied toone form of typewriting machine, with the parts in the position of rest.i

Figure 2 is a mounted finger and its return spring.

Figures 3 and 4 are similar views to Figure 1, showing the machine atthe moment when the escapement is actuated at'the end of travel of thekey.

Figures 5 and 6 show the application of the device to machines otherthan the form rep-.

resented in Figure 1.

Figure 7 is a somewhat diagrammatic perspectiveview of the escapementmechanism on a reatly enlarged scale, and Figure 8 is a section on line8-8, Figure 7.

In most typewriting machines, the-applica-' tion of a pressure on one ofthe keys of the keyboard causes the-universal bar to be actuated, eitherby the key levers, or by the transmission or sub-levers, or by the typebars, and in its turn (independently of any other function it mayperform) it-acts upon the dog rocker of the escapement by means of asuitable mechanism. I

It will be seen from Figure 1 that the dog rocker 1 is adapted to beswung or pushed inwardly or "toward the rear'of the machine detail viewof the pivotally by a rod or plunger 2 acted on by a spring 3 andmounted upon the frame of the machine,

the displacement of the push rod being produced by means of the crossbar 3 shifted by an arm or other member actuated by the universal bar 4.I

According to the invention, the cross bar 3, instead of being actuatedby a rigid member, is actuated by a finger 5 pivoted at 6 upon a leveror arm 7, itself pivoted at 8 and rocked toward the rear of'the machineat each displacement of the universal bar 4.

In the position of rest, the finger 5 is held pressed upon a tappet 9,provided on the lever 7 by a return spring 10.

The tension of this spring is designed to overcome the resistance of themechanism to be actuated, corresponding to the displacement of thecrossbar 3 and the inward movement of the push rod 2. However, as soonthe dogs of the escapement have travelled a sufficient distance they arestopped, in the manner subsequently explained, by a stop 20 in theposition shown in Fig. 3 in which the key 11 has almost completed. itsmovement, that is to say, with the type bar head 12 near the cylinder orplaten 13. In other words, the dog rocker is not actuated to move thedog which is engaged with a tooth of the escapement wheel, out ofcontact with said tooth, until the type bar head has almost reached theprinting point.

It will be understood that at this moment the member 5 pivots about thepin 6, tensioning the spring 10, until the key completes its movement(position shown in Fig. 4). As

soon as the key is released the action of the spring 10 is added to thatof the spring 3 of the push rod 2, the spring 11 of the key lever andthe spring 4* of the universal bar, which springs conjointly tend toreturn the type bars more rapidly than in machines existing at thepresent time.

As shown in Figures 7 and 8, the rocker 1 carrying the dogs 1 and 1swings about an axis determined by two bearing points 23 which aremovable endwise and can be fixed in position by means of screws 23'. Thedog 1" is pivoted at 1 on the rocker and is subjected to the actionof areturn spring 1' that acts on a finger 1 rigidly attachedto anism inorder limited by the stop 1".

Z, the spring 3 associated with the push rod is compressed and the rodcauses the dog rocker 1 to turn about its axis of oscillation in thedirection of arrow Y until dog 1 contacts with the previously-mentionedstop 20, at the same time tensioning the spring 22 which returns therocker. In consequence of this movement, the dog 1 discngagcs the toothn of the ratchet wheel 21 and the dog 1 engages in the space betweensaid tooth n and the next tooth n. The ratchet wheel 21 is'fixed to apinion 21 which, as usual, meshes with the platen carriage rack (notshown), the latteubeing IJulled toward .the

- left in the ordinary way by-thc usual carriage spring, such pullconstantly tending to turn the ratchet wheel in the direction of arrowX.

Immediately the dog licleascs tooth n, the said ratchet wheel turns, andits tooth n engages dog 1" (which has been brought into its path) andforces it to swing about its pivot 1", thereby stretching spring 1',until said dog strikes against a stop 1. This stop 1" is so positionedthat the working face of the dog 1" is stopped at a slight distance fromthatiof dog 1, the latter being situated at that instant outside orbeyond the "plane of the ratchet 21, as represented-in dotted lines inFigure 8.

When the pressure exerted on push rod 2 is removed, the rod is returnedby its spring 3 to its initial. position, the expansion of said sp rinbeing limited by means of a stop 3". The 0g rocker 1 is itself returnedby spring 22; the dog 1 disengaging the tooth n at the very momentwhendog 1" has been brought. into the plane of the ratchet wheel, so thatsaid tooth a, due to the constant tendency of the wheel to turnclockwise (Figure 7), strikes against the working face of dog 1*, whichis positioned slightly in front of the plane of the working face ofdog 1. The dog 1", immediately it leaves the plane of the ratchet, isitself returned to its initial position by the spring 1 whose expansionis The various parts are thus'restored to their original position, andthe ratchet wheel turns one step forward when pressure is again imposed,in the direction of arrow Z, on push rod'2.

It will be seen that this device for actuating the escapement isapplicable to all forms of typewritingmachinesand that it is suflicientto fit the finger 5 with its return spring upon the parts of theescapement controlling mechto obtain the result mentioned above. I InFigs. 5 and 6, two forms of. pivoted finger are shown by way of example.In these figures the parts corresponding to similar parts in Fig. 1 havebeen designated by the same reference numerals. Fig. 5 shows the-*deviceforming-*the sub= ]ect of the invention fitted upon a machine having theuniversal bar acted on by the transmission or sub-levers.

The lever 7 is an arcuate element of angles'ection placed behind thetransmission or sub-levers 14. As soon as a key 11 on the keyboard ispressed down, the transmission lever 1-1 corresponding to this keyswings backwardsin the lnachine, being actuated by the key lever 15. Inmoving, the transmission lever 14 aetuates the type bar, which is notcompletely shown in the drawing, and moves it towards the platen bymeans of a link 16. The transmission lever meets the rocker 7 and swingsit backwards. The finger 5 is mounted on a pivot- 6 riveted to avertical lug on the universal bar 4 to which the rocker 7 is secured,and a spring 10 keeps said finger in contact with the adjustableeccentric stop 9. The end of the finger 5 carries a pivot upon which isadapted to rotate the roller 17 and it is by the contact of the roller17 with the cross-bar 3 that the' movement of the universal bar istransmitted to the mechanismsto be actuated, which are similar to thepreceding mechanisms.

The same 0 erations described in reference to the use of t e device onthe machine shown in Fi s. 1 to 4 are reproduced exactly in'the case sownin Fig. 5.

Figure 6 shows the application of the device according to the inventionto machines having the universal bar acted on by the type 7 bars.'

The universal bar 4 is an arcute member or part of angle-section placedupon the type bar segment. As soon as a key on the keyboard lspresseddown, the lowered key lever 15 actuates an intermediate lever 14 whichmoves the type bar towards the platen 13. The type bar moves theuniversal bar 4 backwards. The latter, by means of a link 18, actuatesthe centrally-located rockin arm or lever 7, at the upper end of whicare arranged'the previously-described fin er 5 and spring 10. All themechanisms 0 the machine are actuated by the pressure exerted by thefinger 5 which may terminate in a roller such as the one shown at 17 inFig. 5. The operations already described are reproduced exactly asbefore.

What I claim is: I

1. In a typewriting machine, a universal bar, an interponent actuatedthereby, .an escapement actuated b said bar throu h said interponentslightly fore the end 0 travel of a key, and a pivoted member on saidin- .terponent adapted to actuate said esca ement and then fyield underresilient contro up to the end 0 travel of said key.

2. In a typewriting machine, a universal bar, an interponent actuatedthereby, an es-' and then yield under resilient control up to the end oftravel of said key, and a roller on said pivoted member. I

3. In a typewriting machine, a universal bar, an interponent actuatedthereby, an escapcment including escapement dogs, a push member operatedby said interponent for actuating the dogs, a pivoted member carried bythe intcrponcnt, and a spring connected be tween said interponent andsaid pivoted member for returning the latter to a position of rest, saidspring ada ted to be stressed at the end of the travel 0 akey and-thuspermit the actuation of the escapement slightly before the end of thetravel of a key.

4. In a typewriting machine, a universal bar, an arm actuated by saidbar, a pivoted member on said arm, a spring connected be tween said armand said member for returning the latter to a position of rest, amovable cross-bar, an escapement including escapement dogs, and a pushmember for actuating said dogs; said pivoted member being adapted toactuate said push member, through said cross-bar, so as .10 actuate theescapement slightly before the end 0 travel of a key and to pivot andthus stretci said spring at the end of the travel of said key.

In testimony whereof I affix my signature.

FERNAND NEPPER;

